Loans Receivable (Summary Of Changes In Accretable Yield) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	$ 628.1		$ 476.1		$ 411.4
New Consumer Loan assignments	586.5	[1]	568.4	[1]	428.1	[1]
Finance charge income	(538.2)		(460.6)		(388.0)
Forecast changes	35.6		39.6		19.7
Transfers	6.1	[2]	4.6	[2]	4.9	[2]
Balance, end of period	718.1		628.1		476.1
Dealer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	508.0		351.6		281.4
New Consumer Loan assignments	538.7	[1]	508.9	[1]	371.6	[1]
Finance charge income	(458.7)		(374.9)		(299.5)
Forecast changes	25.6		30.0		6.3
Transfers	(10.7)	[2]	(7.6)	[2]	(8.2)	[2]
Balance, end of period	602.9		508.0		351.6
Purchased Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance, beginning of period	120.1		124.5		130.0
New Consumer Loan assignments	47.8	[1]	59.5	[1]	56.5	[1]
Finance charge income	(79.5)		(85.7)		(88.5)
Forecast changes	10.0		9.6		13.4
Transfers	16.8	[2]	12.2	[2]	13.1	[2]
Balance, end of period	$ 115.2		$ 120.1		$ 124.5

[1] The Dealer Loans amount represents the net cash flows expected at the time of assignment on Consumer Loans assigned under our Portfolio Program, less the related advances paid to Dealers. The Purchased Loans amount represents the net cash flows expected at the time of assignment on Consumer Loans assigned under our Purchase Program, less the related one-time payments made to Dealers.

[2] Under our Portfolio Program, certain events may result in Dealers forfeiting their rights to Dealer Holdback. We transfer the Dealer’s outstanding Dealer Loan balance and related expected future net cash flows to Purchased Loans in the period this forfeiture occurs.